Accession Number : ADA190569

Title :   An Improved Method for Calculating Power Density in the Fresnel Region of of Circular Parabolic Reflector Antennas.

Descriptive Note : Master's thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING

Personal Author(s) : Mize, Johnnie E

PDF Url : ADA190569

Report Date : Mar 1988

Pagination or Media Count : 97

Abstract : A computer program is presented which calculates power density in the Fresnel region of circular parabolic reflector antennas. The aperture illumination model is the one-parameter circular distribution developed by Hansen. The program is applicable to the analysis of electrically large, center-fed (or Cassegrain) paraboloids with linearly polarized feeds. The scalar Kirchoff diffraction integral is solved numerically by Romberg integration for points both on and perpendicular to the antenna boresight. Axial results cannot be directly compared to any others obtained with this illumination model, but they are consistent with what is expected in the Fresnel region where a quadratic must be added to the linear phase term of the integral expression. Graphical results are presented for uniform illumination and for cases where the first sidelobe ratio is 20, 25, 30, and 35 dB.

Descriptors :   *BORESIGHTING, *COMPUTER PROGRAMS, *FRESNEL ZONES, *ILLUMINATION, *PARABOLIC ANTENNAS, *PHASE(ELECTRONICS), *POLARIZATION, *SIDELOBES, ANTENNAS, CIRCULAR ANTENNAS, DENSITY, DIFFRACTION, FEEDING, THESES, GRAPHICS, LINEAR SYSTEMS, MODELS, POWER, RATIOS, REFLECTORS

Subject Categories : Electrical and Electronic Equipment
      Radiofrequency Wave Propagation
      Computer Programming and Software

Distribution Statement : APPROVED FOR PUBLIC RELEASE